Car models which are sold in several different markets around the world nowadays need to be modified as regards several details, of which the chairs is one. This is due to, among other things, a varying average size, and alternatively average length of the population in various countries and on the several continents. The present invention relates to a chair having several adjustment possibilities for providing a comfortable and ergonomically correct seating position. For such a chair, possibilities are required for adjustment of the seat, the back, the side supports and the lumbar support of the chair.
A chair having a seat which is adjustable in the longitudinal direction is described in U.S. Patent No. 5,370,444, which describes a seat-cushion which is provided with channels which run across the seat between a number of sections. The channels run across the entire width of the seat and from the lower part of the cushion up to a bridge in the upper part of the cushion, which bridge connects adjacent sections. The front section of the cushion rests on a telescopically sliding plate which can be set in relation to the bottom plate of the seat. Thus, the channels between the sections and the bridges which connect adjacent sections provide a certain adjustment of the length of the seat. Drawbacks of this seat include several deep transverse creases which appear in the upholstery in inserted position and an inferior support for load the area which is situated above the channels in most other positions.
U.S. Pat. No. 4,773,703 discloses a similar device in which the sections of the cushion have been situated on a number of individual supporting elements which are reciprocally connected to each other, and are adjustable and lockable in suitable positions. In this regard, the upholstery of the seat is elastically stretched downwards in the space between each element in order not to fold when the seat is adjusted. A drawback regarding this seat is that a bottom plate having several individual elements becomes unnecessarily complicated, and the upholstery must be stretched downwards between the sections.
In U.S. Pat. No. 5,419,614, a mechanism for adjustment of the lumbar support is shown which is in the form of an axle which rotates a cam in the back rest. The axle is fixedly mounted in a frame and has no possibility for vertical adjustment, which is a requirement for an ergonomical adaption.
A side support is disclosed in U.S. Pat. No. 4,883,318 which shows a seat in which the frame has been supplemented with a device for adjustment of the side support in various angles. A drawback associated with this solution is that a comparatively large number of components which are to be built together with the frame, in addition to the adjustment devices, are required for adjustment of the support.
Presently, adjustable chairs are utilized in practically all vehicles, wherein the extent of possible adjustments is widely varying and the solutions to these problems are more or less complicated. A common problem as regards chairs having several adjustment possibilities is that they generally are very complicated and consist of a large number of components, which in turn results in a higher weight. Another problem is that it is necessary for vehicle manufacturers, and alternatively chair manufacturers, to manufacture and stock several different chair sizes, which is due only to the fact that it shall be possible to deliver cars, which are intended for a certain market, with a certain chair size.
In the present invention, a chair is disclosed in which the frame structure is easy to manufacture and consists of few components, but still provides adjustment in several different directions. In this context, adjustment in several directions is taken to mean, for example, adjustment of the length of the chair seat, as well as the height of the back of the chair. By manufacturing each frame in one single piece with integrated attachments and the like, it is also possible to utilize the same frames for both manually and electrically operated chairs.
Furthermore, by way of this invention, and in order to obtain ergonomic adjustment of the chair to different individuals, it is possible to adjust a plurality of aspects of a chair. Exemplarily, the side supports of the chair are made adjustable for the legs, as well as the back, and the angle between the seat and the back is also made adjustable to customize the height and inclination of the seat. The lumbar support is also configured to be adjustable. It is important that the head of a sitting occupant of the seat be situated in the right position in relation to the head rest in the event of a collision; these various adjustment capabilities are configured with this, and other goals in mind.
Furthermore, in order to obtain a light-weight chair which is ergonomically adjustable to a greater number of individuals than is a standard chair of today""s design, the present invention makes it possible to integrate all the above-mentioned functions in a simplified frame made of a plastics material. It is also important to be able to obtain a comfortable and safe driving position, which this chair accommodates. It is also possible to utilize the present chair design in the several different markets around the world thereby decreasing the number of chair sizes which must be manufactured and stocked on a global basis, as well as basis in some markets. In this regard, the number of tools which is required during manufacturer decreases, as well as the stocking space, which results in a more effective production.
The beneficial effects described above apply generally to the exemplary devices, mechanisms and methods disclosed herein for adjustable vehicle seats. The specific structures and methods through which these benefits are delivered will be described in detail hereinbelow.